don't produce type canonical texts with ?extends (EA-47528)

java/java-psi-impl/src/com/intellij/psi/impl/source/tree/SourceUtil.java

@@ -46,7 +46,15 @@ public class SourceUtil {
       @Override
       public void visitLeaf(LeafElement leaf) {
         if (!REF_FILTER.contains(leaf.getElementType())) {
-          buffer.append(leaf.getText());
+          String leafText = leaf.getText();
+          if (buffer.length() > 0 && leafText.length() > 0 && Character.isJavaIdentifierPart(leafText.charAt(0))) {
+            char lastInBuffer = buffer.charAt(buffer.length() - 1);
+            if (lastInBuffer == '?' || Character.isJavaIdentifierPart(lastInBuffer)) {
+              buffer.append(" ");
+            }
+          }
+
+          buffer.append(leafText);
         }
       }
 

java/java-tests/testSrc/com/intellij/psi/MiscPsiTest.java

@@ -239,4 +239,9 @@ public class MiscPsiTest extends LightCodeInsightFixtureTestCase {
     assertFalse(assertInstanceOf(nestedBlock.getNode(), LazyParseableElement.class).isParsed());
   }
 
+  public void testTypeCanonicalText() {
+    PsiType type = JavaPsiFacade.getElementFactory(getProject()).createTypeFromText("some .unknown. Foo<? extends String>", null);
+    assertEquals("some.unknown.Foo<? extends String>", type.getCanonicalText());
+  }
+
 }